I do take into account my age [68] and physical ability, and to tell you the truth it's scary. My body is so broke up from my wild younger years that there isn't much I can do. But I do think about it a lot and try to work out some.
After much consideration, I started to carry in front where my hands are always close to the weapon and I don't have to reach back to access it.
Awareness is of utmost importance in my situation. Believe me, when you get to where I am you think of these things. At least I do.